An apparatus (10) for winding a screen (12) comprises a winding drum (14) for winding the screen (12) which can rotate about an axis of rotation (16) with respect to a fixed frame of reference over more than one revolution between at least one first end-of-travel position and a second end-of-travel position, a motor assembly (30) comprising a motor (32) equipped with a stator (32.1) intended to be fixed to a fixed support (23, 26) and a rotor (32.2) kinematically connected to the winding drum (14). A first measurement assembly (51) comprises a first encoder (46) secured to the rotor (32.2), a first sensor for reading the first encoder (46) and generating a first counting signal when the first encoder (46) turns. First processing means (50) generate, as a function of the first counting signal, a first signal indicative of the position of the screen, which signal is monotonous when the drum moves from the first end-of-travel position to the second end-of-travel position. A second measurement assembly (64) makes it possible to detect at least one indexed position of the drum (14) per revolution of the drum in the fixed frame of reference. A calibration memory (56) stores at least one first calibration value for the first signal indicative of the position of the screen in the indexed position of the drum and at least one first quantitative algebraic comparison between a current value of the first signal indicative of the position of the screen as measured on passing through the indexed position during an observation phase and the first calibration value is delivered.
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1. A winding device for a screen, including a winding drum for winding the screen, which can rotate around an axis of rotation with respect to a stationary frame of reference over more than one revolution between at least one first end-of-travel position and a second end-of-travel position; a motor assembly comprising a motor equipped with a stator intended to be fixed to a stationary support and a rotor kinematically connected to the winding drum; a first measurement assembly comprising a first encoder secured to the rotor, a first sensor for reading the first encoder and generating a first counting signal when the first encoder turns; and first processing means generating, as a function of the first counting signal, a first signal indicative of the position of the screen, the first signal being monotonic when the drum moves from the first end-of-travel position to the second end-of-travel position; a second measurement assembly for detecting at least one indexed position of the drum per revolution of the drum in the fixed frame of reference, a calibration memory for storing at least one first calibration value for the first signal indicative of the position of the screen in the indexed position of the drum; and a comparator for delivering at least one first quantitative algebraic comparison between a current value of the first signal indicative of the position of the screen as measured on passing through the indexed position during an observation phase and the first calibration value.
A winding device controls a screen's position by rotating a winding drum using a motor. The drum rotates more than 360 degrees between end positions. An encoder on the motor's rotor tracks its rotation, generating a signal indicating the screen's position. This signal changes consistently as the screen moves. A second system detects specific drum positions during each rotation. The device stores calibration values relating the screen position signal to these known drum positions. By comparing the current screen position signal to the stored calibration values when the drum reaches these known positions, the device can accurately determine the screen's location and compensate for any inaccuracies.
2. The device according to claim 1 , wherein the second measuring assembly includes a second encoder secured to the drum, a second stationary sensor in the stationary frame of reference to read the second encoder, and second processing means to generate a second signal representative of a passage by the indexed position when the second encoder rotates with the drum.
The screen winding device uses a second encoder on the drum itself for improved position detection. This encoder has a sensor fixed in place that detects when the drum passes specific "indexed" positions. A processing unit generates a signal when the sensor detects these positions. Therefore, the second measurement assembly includes a second encoder secured to the drum, a second stationary sensor in the stationary frame of reference to read the second encoder, and second processing means to generate a second signal representative of a passage by the indexed position when the second encoder rotates with the drum.
3. The device according to claim 2 , wherein the second encoder has no more than eight singularities, and preferably one singularity, readable by the second sensor upon each drum revolution.
To simplify indexed position detection, the second encoder used on the drum in the screen winding device (as described where the second measuring assembly includes a second encoder secured to the drum, a second stationary sensor in the stationary frame of reference to read the second encoder, and second processing means to generate a second signal representative of a passage by the indexed position when the second encoder rotates with the drum) is designed with a minimal number of markings, preferably only one, that the sensor can read per revolution of the drum. This reduces complexity and potential for error.
4. The device according to claim 2 , wherein the drum is guided relative to the stationary support by means of at least one guide bearing, the second encoder being positioned on a rotating part of the bearing.
In the screen winding device (as described where the second measuring assembly includes a second encoder secured to the drum, a second stationary sensor in the stationary frame of reference to read the second encoder, and second processing means to generate a second signal representative of a passage by the indexed position when the second encoder rotates with the drum), the drum is supported by bearings. The second encoder, used to detect indexed positions, is integrated directly into a rotating part of at least one of these guide bearings, simplifying the design and improving accuracy.
5. The device according to claim 1 , wherein the motor assembly includes at least one reduction gear between the rotor and the drum.
The screen winding device incorporates a reduction gear system between the motor's rotor and the winding drum. This allows the motor to operate at a higher speed while providing the necessary torque to move the screen, improving efficiency and control. The reduction gear is positioned between the rotor, which is kinematically connected to the winding drum, and the drum itself.
6. The device according to claim 1 , wherein the device includes at least one rotary vibration damper positioned between the rotor and the drum.
The screen winding device incorporates a rotary vibration damper between the motor's rotor and the winding drum. This damper minimizes vibrations and oscillations, leading to smoother and more precise screen movement and preventing damage to the components. This rotary vibration damper is positioned between the rotor and the drum.
7. The device according to claim 1 , wherein the device includes at least one stationary vibration damper positioned between the stator and the stationary support.
The screen winding device includes a stationary vibration damper placed between the motor's stator and the fixed support structure. This reduces vibrations transmitted from the motor to the surrounding environment, resulting in quieter operation and improved stability. This stationary vibration damper is positioned between the stator and the stationary support.
8. The device according to claim 1 , wherein the motor assembly includes a casing housed in a tube mounted stationary on the stationary support.
The motor assembly of the screen winding device is housed inside a casing. This casing is then mounted within a tube that is fixed to the stationary support structure. This provides protection for the motor and simplifies the overall assembly. The motor assembly includes a casing housed in a tube mounted stationary on the stationary support.
9. The device according to claim 1 , wherein the second measuring assembly comprises a bipolar sensor and the second encoder determines a change in polarity.
The screen winding device utilizes a bipolar sensor in its second measurement assembly to detect the indexed position of the drum. The second encoder is designed to cause a change in polarity when the indexed position is reached, allowing the bipolar sensor to reliably detect the position. Therefore, the second measuring assembly comprises a bipolar sensor and the second encoder determines a change in polarity.
10. The device according to claim 1 , wherein the comparator includes means for generating an offset value depending on at least the first algebraic comparison.
The screen winding device refines its position accuracy by using the algebraic comparison between the current screen position signal and the calibration value at the indexed position to generate an offset value. This offset is then used to correct subsequent position measurements, improving overall precision. Therefore, the comparator includes means for generating an offset value depending on at least the first algebraic comparison.
11. The device according to claim 10 , wherein it further includes a controller for controlling the motor in a subsequent phase based on at least a current value of the first signal indicative of the position of the screen measured in the subsequent phase and the shift value.
After the screen winding device (where the comparator includes means for generating an offset value depending on at least the first algebraic comparison) calculates an offset value, a controller uses this value, along with the current screen position signal, to control the motor in subsequent movements. This allows for precise adjustments to the motor's operation, ensuring accurate screen positioning. The controller controls the motor in a subsequent phase based on at least a current value of the first signal indicative of the position of the screen measured in the subsequent phase and the shift value.
12. The device according to claim 10 , wherein the comparator generates the shift value as a function of several algebraic comparisons between several current values of the first signal indicative of the position of the screen measured upon passage by the indexed position in an observation phase and several calibration values stored in the calibration memory.
To improve the reliability of the position correction, the screen winding device (where the comparator includes means for generating an offset value depending on at least the first algebraic comparison) calculates the offset value based on multiple comparisons between current screen position signals and stored calibration values taken at the indexed position during an observation phase. This averaging approach reduces the impact of individual measurement errors. Therefore, the comparator generates the shift value as a function of several algebraic comparisons between several current values of the first signal indicative of the position of the screen measured upon passage by the indexed position in an observation phase and several calibration values stored in the calibration memory.
13. A method for controlling a device for winding a screen, including a winding drum of the screen, driven by a rotor of a motor, the method comprising: in a calibration phase, at least one calibration value of a rotation angle corresponding to an indexed position of the drum is stored; in an observation phase, the drum is rotated using the motor while measuring a current value of the rotation angle of the rotor of the motor and detecting the passage of the drum by the indexed position, and at least one quantitative comparison is done between the current value when the drum passes by the indexed position and the calibration value.
A method for controlling a screen winding device involves storing a rotation angle as a calibration value that corresponds to an indexed drum position. During operation, as the motor rotates the drum, the method measures the current rotation angle of the motor's rotor. When the drum reaches the indexed position, the method compares the current rotation angle to the stored calibration value.
14. The method according to claim 13 , wherein in the calibration phase, the drum is driven with the motor between a first end-of-travel position and a second end-of-travel position in a reference rotation direction and as many calibrations are stored as there are passages of the drum by the indexed position.
In the method for controlling the screen winding device, the calibration phase involves driving the drum between its end positions using the motor. Every time the drum passes the indexed position during this calibration movement, the rotation angle is recorded and stored as a calibration value. Therefore, as many calibrations are stored as there are passages of the drum by the indexed position.
15. The method according to claim 14 , wherein in the observation phase, the drum is rotated in the reference direction, and as many quantitative comparisons are done between the current value when the drum passes by the indexed position and the calibration value as there are passages of the drum by the indexed position.
In the method for controlling the screen winding device, during the observation phase, the drum rotates in the same direction as the calibration phase. Each time the drum passes the indexed position, a quantitative comparison is made between the current rotation angle and the stored calibration value for that position. Therefore, as many quantitative comparisons are done between the current value when the drum passes by the indexed position and the calibration value as there are passages of the drum by the indexed position.
16. The method according to claim 15 , wherein a shift value is determined over one revolution or more than one revolution of the drum, based on several of said comparisons.
To refine the accuracy in the screen winding device control method, a shift value is calculated after one or more drum revolutions. This value is based on multiple comparisons between current rotation angles and stored calibration values collected during the observation phase. This shift value is then used to correct subsequent position measurements. Therefore, a shift value is determined over one revolution or more than one revolution of the drum, based on several of said comparisons.
17. The method according to claim 13 , wherein a new position value of the motor is determined upon each passage by an indexed position as a function of the current value of the first signal indicative of the measured position of screen and the shift value determined in the observation phase for one or more indexed positions.
The control method for the screen winding device updates the motor's position value each time the drum passes the indexed position. This update is a function of both the current screen position signal and the shift value that was determined during the observation phase for one or more indexed positions. Therefore, a new position value of the motor is determined upon each passage by an indexed position as a function of the current value of the first signal indicative of the measured position of screen and the shift value determined in the observation phase for one or more indexed positions.
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June 6, 2014
May 30, 2017
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